1-cyclohexenyl isocyanide

Cyclohexenyl Isocyanide-resin Carbonate Convertible Isocyanide-resin... 

The synthesis started with an Ugi four-component condensation involving protected glutamic acid 242, aldehyde 243, methylamine and cyclohexenyl isocyanide 244. The resulting dipeptide product 245 was first hydrolyzed to acid 246, which was then coupled with amine 247. Further derivatizations of the resulting tripeptide 248 afforded the desired natural product. 

Armstrong et al. [98] formed various products of the type 31C by hydrolyzing under mild conditions the products of the U-4CRs with A -cyclohexenyl isocyanide 13d [99] as a particularly suitable educt. Many different products of the types 31Ca-c and the heterocycles 38a-c can be obtained from 18A. The first such reactions were carried out in 1963. The pharmaceutically interesting products 38c can also be formed directly by a U-4CR of anthranilic acid [100]. 

Similar results have been described in relation to the synthesis of 1-cyclohexenyl isocyanide Armstrong stated that ... triphosgene as a dehydrating agent was superior to the phosphorus oxychloride called for by Ugi [38]. 

Figure 3-11 four-component Ugi reaction reported by Keating and Armstrong. A combinatorial mixture of the intermediate cyclohexenyl amide can be split into several portions, and each can be further reacted to give a variety of products, all of which will be combinatorial. (Reaction redrawn from description from Keating. T. A., and Armstrong. R. W Molecular diversity via a convertible isocyanide in the Ugi four-component condensation J. Am. Chem. Soc. 117 7842-7843. 1995.)... 

A very versatile application of the Ugi reaction has been reported by Keating and Armstrong [42]. They use cyclohexenyl isonitrile (1) as a universal isocyanide in an Ugi four-component condensation. The other components are varied. The reaction products, 2-acylamino-alkanoic acid amides of generic structure 2, can undergo a number of further reactions leading in parts to new types of structures and increased diversity (Scheme 3.4). If a resin with free alcoholic groups is used the acylaminoacyl moiety can be bound to the solid phase before it is subjected to further modifications (resin capture). 

Cyclohexene-l,4-diol, 586 Cyclohexene epoxide, 71, 333, 466, 488 Cyclohexene-3-ol, 428 Cyclohexenone, 21 Cyclohexenones, 371 2-(3-Cyclohexenyl)ethanol, 637 N-Cyclohexenylmotpholine, 433 Cyclohexylamine, 230 Cyclohexylideneacetaldehydes, 357 Cyclohexylidenecyclohexane, 171 Cyclohexylidenethyl bromide, 327, 328 Cyclohexyl isocyanide, 129, 152... 

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